This invention is a wick assembly for cleaning excess liquid toner from a xerographic plate, the mechanism comprising a sheet of wicking material fed from a roll and wiped across the back of the plate to absorb excess toner.
In a xerographic liquid development system, liquid toner must be transferred from the development fountain to the xerographic plate, and from there to the paper to form an image. However, in addition to the image toner, there is always excess toner which is transferred to the working surface, sides and back of the plate. This toner, if not removed, will spread around the interior of the cabinet by the numerous mechanical devices, making the interior unsightly, and leading to a mechanical and electrical lack of reliability.
There are three main reasons for excess toner being present in the cabinet. One is that the top of the standing wave of toner at the fountain is higher than the lower surface of the plate, so that as the leading and trailing edges of the plate pass over the fountain, some toner is deposited on the top of the plate. Second, in this system the transfer of toner from the plate to the paper is accomplished under pressure, the pressure being applied by a flexible transfer wiper which scrapes along the bottom of the paper as it advances, along with the plate, through the transfer station. As the trailing edge of the paper passes the transfer line, some toner may be squeezed out from under the trailing edge of the paper. Finally, as the trailing edge of the plate passes the wiper, the edge of the wiper will snap up to its rest position, possibly throwing toner into the interior of the cabinet.
What is required is a cost effective apparatus for removing this excess toner.